1. Field of the Invention
The present invention relates to a digital camera having a camera body. More particularly, the present invention relates to a digital camera, in which a lens assembly is connectable with a camera body, and a lens mount mechanism of the camera body can be protected from dust, liquid or other foreign material.
2. Description Related to the Prior Art
A digital still camera is known in the field of optical instruments. A CCD image sensor as image pickup device records an image of an object to generate image data by digital conversion. Image data is written to a built-in memory or a memory card as external storage medium. U.S. Pat. No. 6,742,943 (corresponding to JP-A 2004-109970) discloses one example of the digital still camera in which a lens assembly is used as an exchange lens for focusing an object image of the CCD image sensor. A selected one of plural types of exchange lenses can be used according to intention of a user, for example wide-angle lens or telephoto lens.
In a lens exchange type of the digital still camera, it is likely that dust, liquid or the lid may enter a camera body through a lens mount mechanism for the lens assembly. If foreign material enters the camera body, it may stick on the CCD image sensor and create a portion of dirt in an image, or cause difficulty or damage in the operation of the camera body. In view of this, U.S. Pat. No. 6,742,943 (corresponding to JP-A 2004-109970) discloses an openable cover for closing an opening of the lens mount mechanism while the lens assembly is removed. Entry of dust or the like is prevented through the lens mount mechanism.
However, the cover disclosed in the document opens and closes the opening of the lens mount mechanism by simply sliding or rotating a panel shaped device as the cover. There is no suggested prevention of entry of liquid. It is conceivable to use a removable cap, associated with the lens mount mechanism, for covering and closing the opening in a fluid tight manner. However, there arises a problem in low operability of the digital still camera because of complicated operation for loading and unloading the cap.